NTFS supports multiple data streams, in which the stream name identifies a new data attribute on the file. Each data stream is an alternate set of file attributes. Streams have separate opportunistic locks, file locks, allocation sizes, and file sizes, but files can be shared.
This feature enables data to be managed as a single unit. Using multiple data streams, a file can be associated with more than one application at a time, such as Microsoft Word and WordPad.
When you copy an NTFS file to a FAT volume, such as a floppy disk, data streams and other attributes not supported by FAT are lost.